Automatic train control



E. CHABUT.

AUTOMATIC TRAIN CONTROL. APPLICATION FILED :UNE H. 19|?.

1 ,31 0,059, Patented July 15, 1919.

`2 SHEETS-SHEET l.

E. CHABOT.

Amon/:Anc TRAIN coNTRoL.

APPLICATION FILED IUNE il. 191?. 1,3 1 0,059.

12s 27's 124 Y 224 4:.

l.?2 IIS Patented July 15, 1919.

2 SHEETS-SHEET 2.

j@ Q/f/AMN EPHRAIM GHABOT, OF N ASHUA, NEW HAMPSHIRE.

AUTOMATIC TRAIN CONTROL.

Specification of Letters Patent.

Patented July 15, 1919.

Application led June 11, 1917. Serial No. 173,939.

To aZZ whom it may concern.'

Be it known that I, EPHRAIM CHAo'r, of Nashua, in the county of Hillsborough and State of New Hampshire, have invented certain new and useful Improvements in Automatic Train Controls, of which the following is a specification.

This invention relates to means for automatically stopping trains, if for any reason the engineer fails to observe the signals which are set against him, said means being of the general type disclosed in Letters Patent No. 1,223,310, granted to me April 17, 1917.

The object of my present invention is to provide improvements in certain parts of the system which are carried by the engine cab, With a view to economy of construction and ease and efiiciency of operation, as Will more fully appear hereinafter.

lVith these and other objects in view, the invention consists of certain novel features of construction, as will be more fully described and particularly pointed out in the appended claims.

Of the accompanying drawings:

Figure 1 is a view similar to Fig. 1 of said Patent 1,223,310, showing diagrammatically suitable relative positioning for the different members of the cab system, and the pipe connections.

Fig. 2 represents a section on line 2 2 of Fig. 1, on a larger scale, to illustrate the pressure controlling mechanism which I prefer to that shown in Fig. 3 of said patent.

Fig. 3 represents a section on line 3 3 of Fig. 2.

Fig. 4 is a sectional elevation of the ren lease valve and its casing which is mounted on the top of the casing of the speed-controlled mechanism shown at the bottom of Fig. 1.

Fig. 5 is a sectional elevation of a steam controlling valve of the balanced type, said valve being, in practice, connected on one side to the boiler and on the other side to the engine, the steam pipe connections themselves being omitted in both Figs. 1 and 5.

Fig. 6 is a sectional elevation of the valve mechanism which is interposed in the train pipe connections for the air brakes.

Fig. 7 is a sectional elevation of the valve mechanism to enable the brake and steam valves to be released when the train speed has been sufficiently reduced.

Similar reference characters indicate similar parts and connections in all of the views.

It may facilitate an understanding of the following description if it be understood at the outset that all reference numerals below 100 indicate parts, the construction and operation of which are substantially the same as in said Patent 1,223,310, While reference numerals above 100 indicate parts embodied in my present improvements.

Referring first to Fig. 1, it is to be understood that tho following parts are or may be, in construction and operation, the same as in Patent. 1,223,310, viz: the signal post 20, semaphore signal 21, arm 22, bracket 23, casing 24, tripping arms 27, 29, shaft 30, lever arm 31, link 32, engine cab 33, engine Wheel 34, and axle 3G. The casing 37 of the air pressure controlling mechanism is supported by a standard 33 rising from the cab roof, said casing supporting shafts 40 and 43 having arms 39, 42, respectively, said arms being held normally in the positions shown in Fig. 1 by the mechanism shown in Figs. 2 and 3. The shafts 40, 43, respectively, carry cams 41, 44, each cam operating in a stirrup 110 having a guiding pin 111 sliding in a fixed guide bracket 112, said stirrups being pivotally connected to two levers 202, 203 which act as props for tvvo piston rods 204. 205, presently described. Each shaft is made of tvvo sections in alinement, the two sections being connected by a U-shaped block 113 similar to a crank, said block having tvvo cross pins 114. Bearing against each pair of pins 114 is a block 115, the tvvo blocks having grooves engaging said pins, and having slidably interengaged Shanks. one shank entering the other. A spring 11G surrounding said shank and bearing against collars of the two blocks 115 exerts a constant pressure to cause the blocks to bear on both pins 114 of both pairs and normally so hold the two shafts that one arm 39 extends down and the other arm 42 extends up, to be engaged by one or the other of the tripping arms 29 or' 27 in the same manner and for the saine purpose as explained in said Patent 1,223,310. Whenever either shaft 40, 43, is rocked, due to its arm 39 or 42 contacting with the obstruction presented by one or the other of the signal-controlled tripping arms 29 or 27, the cam of such shaft acts to shift one of the stirrups 110 and move one or the other of the props 202, 203, out of alim-nient with a piston rod 204, 205.

The piston rods 204, 205, respectively ral-ry pistons 206, 207, ontrolling ports 203, 209, rouimunirating with pipes 210, 211. A spring 11i is ('oiled around each piston rod and exerts pressure against the piston to ward the luft in Fig. 2.

The pipes 210, 211. have, respectively, branch pipes 212, 213 (Figs. 1 and 5) leading to the upper portion of steam-controlling valve mechanism the casing of which is indicated at 118, the details of which mlmnisrn Will be presently described.

As shown 1n Figs.. 1 and 6, the pipes 210, 211 lead to cylindrical chambers provided in a casing 119. In one cylinder is a piston 214 the stem or rod of which carries a valve 217 adapted to ooact with valve scat 216 or to 'lose port 222 which communicates With a pipe 220. a spring 120 tending to hold it in the latter position. 1n the other cylinder is a piston 21:3 the stein or rod of which rarries a vulve 219 adapted to coact with valve scat 21S or to close a port 221 Whirh conununi rates with pipe 220, a spring 121 tending to hold it in the latter position. The chambers behind the valve seats 218, 216, comn'iunicate with each other. The usual air supply pipe 240 communicates with one chamber and the train pipe 241 for the usual air brakes coinmunirates With the other.

Referring new to Fig. 5 the balanced steam valve 242 has its stem 122 provided with a piston fitting the cylinder in casing 118, said stem being longitudinally bored and receiving the stem 226 O f an upper piston 224, the latter having an upwardly extending stem or shank 123 having n, head 225. The stem 123 extends through a fixed apertured collar or washer 124 which acts as a stop for head 225, to determine the lowermost position to which piston 224 can be shifted as hereinafter explained.

Pivotally mounted in the casing 125 (Figs. 1 and 7) is a lever handle 2.2.7 normally held in the position shown by a spring 126. Pivotally Connected at 127 to the handle 227 is a bumper rod 228 normally in alinement with the rod 229 of a piston 128.11m cy1- inder 129. A link 130 connects bumper rod 228 With the rod of a piston 230 in cylinder 131, a spring 231 normally holding the parts in the position shown by full lines in Fig. 7. A pipe 232 connects the side of cylinder 129 with the pressure chamber 243 in casing 37 (Figs. 1 and 2). A ipe 233 connects the end of cylinder 129 W-itlxi3 air reservoir 235 and also with a pipe 23.4 presently described. A pipe 236 is connected with the top of cylinder 131. The two pipes 234, 236. lead to the top of a valve casing 1.32 (Figs. 1 and 4) mounted on a housing 133 supported by thc truck of the engine,4 the axle 36 extending through said holsising. Secured to the axle is a follar 134 to which are pivoled two elbow levers 135 varuviug weights 136. The elbow levers are connected l,i one` o1' more links with :1 sleeve 137 slidably mounted on .ftXle 36 and having an annular groove in which are one or mole rolls or blocks connorted lo the lower end o'f a lever 245 pivotcd at 133. l have not illustrated all oi`l the small details of the mechanism iurlosed in housing 133, as any other suitable device muy he employed for .shitting the position ot' lever 245 by centrifugal Vlorce due to the spoed of the engine or train.

The upper end of the lever 245 engages a slide 237 (Fig. 4) mounted on plate 139, said slide having a cavity in its under side to control ports 233, 239. the latter communi cating by a port 140 with pipe The pipe 234 conm'iunirates with the chamber in casing 132 above the slide 237.

Normally, when the train is running :il iull required spoed, air pressure Jfrom rcsrr Voir 235 (Fig. 1) :iris through pipe 233. cylinder 129 (Fig. 7) and holds pistou 123 in position to permit the pressure to he exert-cd through pipe 232 to chamber 243 (Fig. 2). And at this speed, the Weights 136 (Fig. 1) of the centrifugal controller mechanism are thrown out and the grooved sleeve 137 is shifted, to cause lever 245 to shift slide 237 so that it instead of occupying the Fig. 4 position, is far enough to the left to uncover port 239. This perniits air pressure to be transn'iittcd from reservoir through pipe 234 (Figs. 1 and 4) to the chamber iu casing 132, through ports 239 and 140, and pipe 236. to cylinder 131, (Fig. 7) depressing piston 230 and lowering bumper rod" 223 to the dotted line position.

When the semaphore` 21 is set to position to signal the engineer to stop, it results iu causing tripping arm 29 to occupy a dosition as shown in Fig. 1. as explained in IPat ent 1,223,310. If now the engineer fails to stop his train, the Contact lever 39 strikes arm 29 and is swung backwardly and its shaft 40 rocks and causes cam 41 to act on the stiirup connected with prop 202 to release piston rod 204. Air pressure from chamber 243 (Fig. 2) then acts on piston 206 to shift it past port 208, and air passes through pipe 21.0 and acts on piston 214 (Fig. 6) to close valve 217 on seat 216, thus shutting oli the pressure froni supply pipe 240 to. train pipe 241, and permitting exhaust through pipe 220, thereby applying the brakes. At the same time air pressure passes through pipe 212 (a. branch of pipe 210, Fig. 1) to act on piston 223 (Fig. 5) to close steam valve 242, thus shutting oit the motive force. It is to be understood that the pressure in chamber 243 is supplied from reservoir 235 (Fi 1) through pipe 233, cylinder 129 (Fig. 7% and pipe If the signal 21 is set to caution position.,

the tripping arm 27, instead of arm 29, is projected horizontally as explained in said patent. If new the engine is passing, the

Contact lever 42 Will be swung backwardly, and its shaft 43 rocked, and cam 44 will cause prop 203 to release piston rod 205 (Fig, 2). Air pressure then shifts piston 207 and uncovers port 209, and air passes through pipe 211 and acts on piston 215 (Fig. 6) to shift valve 219 over to seat 218, shutting oii pressure from supply 240 and reducing the pressure in the train pipe 241 by permitting exhaust through port 221 and pipe 220. As the port 221 is much smaller than the opening within seat 222 the pressure in the train pipe will reduce gradually, thereby applying the brakes comparatively slowly. At the same time, air pressure passes through pipe 213 (a branch of pipe 211, Fig. 1) to act on piston 224 (Fig. 5) to shift steam valve 242 toward closing position. The valve 242 does not entirely close however, the extent 0f movement of piston 224 is limited by Contact of its stemhead 225 with the stop collar 124. Therefore the motive force is not entirely out ofl".

W'hen the speed of the train has been so reduced that the centrifugal controller mechanism on axle 36 causes lever 245 F ig. 4) to move slide 237 to the F ig. 4 position, air pressure on piston 230 (Fig. 7) is at once reduced because air can escape through pipe 236, ports 140 and 239 and outlet or escape port 238. The spring 231 then raises iston 230 and brings bumper rod 228 to the full line position of Fig. 7 Where it is in alinement with piston rod 229. The engineer can now (when the rules of the road permit or require it) resume speed by operatinnr the handle 227 to shift piston 128 to eut olf the passage of air from pipe 233 to pipe 232 and simultaneously open communication to an escape or exhaust port 244 in cylinder 129 so that pressure is immediately reduced in pipe 232 and (see Figs. 1 and 2) in chamber 243 so that the pistons 206, 207, can be returned to the positions shown in Fig. 2 by their springs 117. The props 202, 203, are returned to their holding positions shown in said Fig. 2 by the spring 116 acting on `blocks 115 and, through pins 114 and blocks 113, rotating the shafts 40, 43 or either one of them which has been previously acted upon) to cause the cams to act on the stirrups to return the props to the holding positions shown in Fig. 2. There can now be no air pressure in either of the pipes 210, 211, 212, 213., and therefore the brake valves of .this system- Will be opened by theirv springs. and steam pressure acting on the lower end of valve 242 will raise it and permit unrestricted resumption of speed.

If the speed is not reduced to that which is determined by the centrifugal controller in housing 133 (Fig. 1) as necessary to insure the required reduction, the lever 245 will still hold the slide 237 so that port 239 is uncovered sufiiciently to allow pressure from reservoir 235 to pass through pipe 234 (Figs. 1 and 4) and said port 239, and through port 140 and pipe 236 to act on piston 230 (Fig. 7) and prevent the bumper rod 228 from assuming a position in line with piston rod 229. Therefore the handle 227 can not be operated to attain the above described resumption of speed prior to the engine having been slowed down to that speed which has been predetermined as proper and safe.

It will now 'be understood that an'engine can not run past a signal that is set against it Without being stopped automatically, but if the engineer has observed the signal and previously slowed down his train to the required ratc. then the operation of the engine still lies within his control.

I have shown and described the mechanism as beingr arranged to shut off the power and also at the same time apply the brakes but my mechanism may be arranged to either shut off the power' without applying the brakes, or apply the brakes without shutting off the power, if desired. If, however, only one of these operations is effected the application of the brakes is considered the most effective.

I do not limit myself to a steam engine. Obviously the invention may be utilized for the automatic stripping 0r slowing down of trains or motors which are driven by a motive force or power other than steam. For instance, to adapt the invention to an electric motor or train employing` a wellknown air brake system, the only necessary change would be to omit the balanced steam valve 242 and substitute therefor any suitable or Well-known arm or lever for controlling the electric current. By the term engine employed in the claims, I mean to include either a locomotive or train, whether the motive force employed be steam, electricity or any other power.

I desire to emphasize the fact that my invention is in no vv-ay dependent upon any electric current and is not affected by climatic or weather conditions. So longV as the well-known and widely used semaphore signal systems and air brake systems of daily use are in operative conditions, my improvements will effect automatic stopping or slowin .q down, as they can not be affected b v any short circuiting of electric currents or failure of batteries on the engine or tra-in. or by rain. ice, snow, or other road-bed accumulations or obstacles.

Having now described my invention, I claim:

1. In a mechanism for automatically ccntrolling,r an engine, a brake control mechanism including a casing having tWo cylindrical chambers and two pairs of ports with oppositely facing valve seats, a piston in each of said chambers and having a stem provided with a double faced valve, the spaces at the inner sides of the valves communicating with each other and with an outlet, thc spaces at the outer sides of the valves being in communication with the air brake train pipes, springs for normally holding the pistons with the valves on the inner valve seats, and signal-controlled mechanism for admitting air pressure to one or the other of said chambers to act on the piston thereof to shift its valve to its opposite seat.

i2. In mechanism for automatically controlling an engine, a brake control mechas nism including a casing having two cylinA drical chambers and two pairs of ports with oppositely facing valve seats, the inner port ot one pair being smaller than its opposite outer port, a piston in cach of Said chambers and having a stem provided with a double faced valve, the spaces at the inner sides of the valves communicating with each other and with an outlet, the spaces at the outer sides of the valves being in communication with the air brake train pipes, springs for normally holding the pistons with the valves on the inner valve seats, and signalcontrolled mechanism for admitting air pressure to one or the other of said chambers to act on the piston thereof toI shift its valve to its opposite seat.

3. In mechanism for automatically controlling an engine, a cylinder, two pistons in the cylinder one of the pistons being limited to a lesser range of movement than the other, a power-controlling member operatively connected to bo-th of said pistons, and signal-controlled mechanism for admitting air pressure to cause said member to be actuated by one or the other of said pistons.

4. In mechanism for automatically controlling an engine, a cylinder, two pistons in the cylinder having telescoping stems, a power-controlling member connected with one of said stems and si :il-controlled mechanism for admitting alr pressure to cause said member to be actuated by one or the other of said pistons.

5. In mechanism for automatically controlling an engine, a power-controlling member, a cylinder, two pistons in said cylinder connected to said member to shift it, one piston being limited in its traverse to only partly move the power-controlling member, a source of pressure, and independent signal-controlled connections for actuating one or the other of said pistons.

6. In mechanism for automatically controlling an en ine, a power-controlling member, a cylin er, a stem provided with a piston in said cylinder, a second piston in the same cylinder having a stem slidably engaged with the first-mentioned stemt, means for limiting the traverse of the second piston, a source of pressure, and indef pendent signal-controlled connections for actuating one or the other of said pistons.

7. The combination with means for automatically and pncumatically effecting the application of the brakes of an engine, of means whereby manual control of the brakes can be maintained when the speed is below a predetermined rate, said means including a pneumatic cut-oil", a manually operable device or shifting said cut-off, and an air pressure mechanism for preventing or permitting effective operation of said device.

8. The combination with means for automatically and pneun'iatically effecting the application ot the brakes of an engine, oi means whereby manual control of the brakes can be maintained when the speed is below a pre-determined rate, said means including a pneumatic cut-off` a manually operable device for shifting said cut-ofi?, an air pressure mechanism, and a centrifugal governor to control said air pressure mechanism to prevent or permit effective operation of said device.

9. The combination with means for automaticall' and pneumatically effecting the application of the brakes of an engine, of means whereby manual control of the brakes can be maintained when the speed is below a pre-determined rate, said means including a cylinder having an escape port, pipes connected to said cylinder, a piston in said cylinder adapted to cut oill communication between said pipes and open communication between said escape port and one of the pipes, a handle having a bumper rod to actuate said piston and means for holding said bumper rod out of operative position until speed is reduced to pre-determined rate.

10. The combination with means for automatically and pneumatically effecting the application of the brakes of an engine, of means whereby manual control of the brakes can be maintained when the speed is below a pre-determined rate, said means including a cylinder having an escape port, pipes connected to said cylinder, a piston in said cylinder adapted to cut olf communication between said pipcs and open communication between said escape port and one of the pipes, a handle having a bumper rod to actuate said piston, a piston having a connecs tion with the bumper rod to determine the position of the latter, and speed controlled pressure means for actuating the last-mentioned piston.

11. The combination with means for automatically and pneumatically effecting the application of the brakes of an engine, of means whereby manual control of the brakes can be maintained when the speed is below a pre-determined rate, said means including a slide valve, a lever directly engaging said valve to slide it, means operated variably according to the rate of speed for actuating and controlling said lever, and ports controlled by the valve.

12. The combination with means for automatically'- and pneumatically effecting the application of the brakes of an engine, of means whereby manual control of the brakes can be maintained when the speed is below a pre-determined rate, said means including a slide valve, a lever directly engaging said valve to slide it, means operated variably according to the rate of speed for actuating and controlling said lever, ports controlled by the valve and means and connections whereby manual release of the brakes will be permitted or prevented according to the position of said valve on its seat.

13. In mechanism for automatically controlling an engine, an air pressure controlling mechanism comprising a casing having a passageway for air under pressure, a piston valve for controlling said passageway said valve having a stem a lever prop for said stem, a stirrup pivotally connected with said prop, a shaft having a cam to actuate said stirrup to swing the prop laterally, and signalcontrolled mechanism for actuating said shaft.

14. In mechanism for automatically controlling an engine, an air pressure controlling mechanism comprising a casing having a passageway for air under pressure, a pair of piston valves for independently controlling said passageway said valves having stems, a lever prop for each of said stems, stirrups pivotally connected with Said props, shafts having cams to actuate said stirrups to swing the props laterally, and signal-controlled mechanism for actuating said shafts independently.

In testimony signature.

whereof I have alixed my EPHRAIM CHABOT.

Copies ot this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

